METALLIC BOND — force that holds atoms together in a metallic substance. Such a solid consists of closely packed atoms. In most cases, …Britannica English vocabulary

LIGAND FIELD THEORY — in chemistry, one of several theories that describe the electronic structure of coordination or complex compounds, notably transition metal complexes, …Britannica English vocabulary

IONIZATION — in chemistry and physics, any process by which electrically neutral atoms or molecules are converted to electrically charged atoms or …Britannica English vocabulary

ELECTRONIC CONFIGURATION — also called Electronic Structure, the arrangement of electrons in energy levels around an atomic nucleus. According to the older shell …Britannica English vocabulary

ELECTRON TUBE — also called vacuum tube, or valve, device used in electronic circuitry to control a flow of electrons. Such devices include …Britannica English vocabulary

ELECTRON — lightest stable subatomic particle known. It carries a negative charge which is considered the basic charge of electricity. An electron …Britannica English vocabulary

ELECTROLUMINESCENCE — production of light by the flow of electrons, as within certain crystals. Electroluminescence is one of the few instances in …Britannica English vocabulary

ELECTRICITY — the phenomenon associated with stationary or moving electric charges. Electric charge is a fundamental property of matter and is borne …Britannica English vocabulary

ELECTRIC CHARGE — quantity of electricity that flows in electric currents or that accumulates on the surfaces of dissimilar nonmetallic substances that are …Britannica English vocabulary

CLUSTER — Atoms and molecules are the smallest forms of matter typically encountered under normal conditions and are in that sense the …Britannica English vocabulary

CHEMICAL BONDING — any of the interactions that account for the association of atoms into molecules, ions, crystals, and other stable species. When …Britannica English vocabulary

BREMSSTRAHLUNG — (German: braking radiation), electromagnetic radiation produced by a sudden slowing down or deflection of charged particles (especially electrons) passing through …Britannica English vocabulary

BAND THEORY — in solid-state physics, theoretical model describing the states of electrons, in solid materials, that can have values of energy only …Britannica English vocabulary

ATOM — smallest unit into which matter can be divided without the release of electrically charged particles. It also is the smallest …Britannica English vocabulary

ATMOSPHERE — gaseous envelope that surrounds the Earth. Other planets of the solar system, as well as a few of the large …Britannica English vocabulary

GUNN EFFECT — high-frequency oscillation of electrical current flowing through certain semiconducting solids. The effect is used in a solid-state device, the Gunn …Britannica English vocabulary

ATOMIC STRUCTURE AND INTERACTIONS — Atomic structure and interactions Electrons As noted above, the electron was the first subatomic particle discovered. Its interactions determine atomic …Britannica English vocabulary